Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency

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Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency
Other namesLCHAD deficiency
Autorecessive.svg
Long-chain 3-hydroxyacyl-coenzyme; A dehydrogenase deficiency has an autosomal recessive pattern of inheritance.

Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency is a rare autosomal recessive fatty acid oxidation disorder [1] that prevents the body from converting certain fats into energy. This can become life-threatening, particularly during periods of fasting.[ citation needed ]

Contents

Schematic demonstrating mitochondrial fatty acid beta-oxidation and effects of LCHAD deficiency LCHAD deficiency.svg
Schematic demonstrating mitochondrial fatty acid beta-oxidation and effects of LCHAD deficiency

Symptoms and signs

Typically, initial signs and symptoms of this disorder occur during infancy or early childhood and can include feeding difficulties, lethargy, hypoglycemia, hypotonia, liver problems, and abnormalities in the retina. Muscle pain, a breakdown of muscle tissue, and abnormalities in the nervous system that affect arms and legs (peripheral neuropathy) may occur later in childhood. There is also a risk for complications such as life-threatening heart and breathing problems, coma, and sudden unexpected death. Episodes of LCHAD deficiency can be triggered by periods of fasting or by illnesses such as viral infections.

Genetics

Mutations in the HADHA gene lead to inadequate levels of an enzyme called long-chain 3-hydroxyacyl-coenzyme A (CoA) dehydrogenase, which is part of a protein complex known as mitochondrial trifunctional protein. Long-chain fatty acids from food and body fat cannot be metabolized and processed without sufficient levels of this enzyme. As a result, these fatty acids are not converted to energy, which can lead to characteristic features of this disorder, such as lethargy and hypoglycemia. Long-chain fatty acids or partially metabolized fatty acids may build up in tissues and damage the liver, heart, retina, and muscles, causing more serious complications.

Diagnosis

Prognosis

A 2001 study followed up on 50 patients. Of these 38% died in childhood while the rest suffered from problems with morbidity. [2]

See also

Related Research Articles

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Mitochondrial trifunctional protein deficiency Medical condition

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Very long-chain acyl-coenzyme A dehydrogenase deficiency Medical condition

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ACADVL Protein-coding gene in the species Homo sapiens

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Short-chain acyl-coenzyme A dehydrogenase deficiency Medical condition

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Acyl-CoA

Acyl-CoA is a group of coenzymes that metabolize fatty acids. Acyl-CoA's are susceptible to beta oxidation, forming, ultimately, acetyl-CoA. The acetyl-CoA enters the citric acid cycle, eventually forming several equivalents of ATP. In this way, fats are converted to ATP, the universal biochemical energy carrier.

HADHA

Trifunctional enzyme subunit alpha, mitochondrial also known as hydroxyacyl-CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase, alpha subunit is a protein that in humans is encoded by the HADHA gene. Mutations in HADHA have been associated with trifunctional protein deficiency or long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency.

3-hydroxyacyl-coenzyme A dehydrogenase deficiency is a rare condition that prevents the body from converting certain fats to energy, particularly during fasting. Normally, through a process called fatty acid oxidation, several enzymes work in a step-wise fashion to metabolize fats and convert them to energy. People with 3-hydroxyacyl-coenzyme A dehydrogenase deficiency have inadequate levels of an enzyme required for a step that metabolizes groups of fats called medium chain fatty acids and short chain fatty acids; for this reason this disorder is sometimes called medium- and short-chain 3-hydroxyacyl-coenzyme A dehydrogenase (M/SCHAD) deficiency.

ACADSB Protein-coding gene in the species Homo sapiens

ACADSB is a human gene that encodes short/branched chain specific acyl-CoA dehydrogenase (SBCAD), an enzyme in the acyl CoA dehydrogenase family.

Fatty-acid metabolism disorder Medical condition

A broad classification for genetic disorders that result from an inability of the body to produce or utilize one enzyme that is required to oxidize fatty acids. The enzyme can be missing or improperly constructed, resulting in it not working. This leaves the body unable to produce energy within the liver and muscles from fatty acid sources.

Hydroxyacyl-Coenzyme A dehydrogenase

Hydroxyacyl-Coenzyme A dehydrogenase (HADH) is an enzyme which in humans is encoded by the HADH gene.

References

  1. Reference, Genetics Home. "LCHAD deficiency". Genetics Home Reference. Retrieved 2017-02-27.
  2. Boer, Margarethe E. J. den; Wanders, Ronald J. A.; Morris, Andrew A. M.; IJlst, Lodewijk; Heymans, Hugo S. A.; Wijburg, Frits A. (2002-01-01). "Long-Chain 3-Hydroxyacyl-CoA Dehydrogenase Deficiency: Clinical Presentation and Follow-Up of 50 Patients". Pediatrics. 109 (1): 99–104. doi:10.1542/peds.109.1.99. ISSN   0031-4005. PMID   11773547.